2 /* The industrial I/O core
4 * Copyright (c) 2008 Jonathan Cameron
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published by
8 * the Free Software Foundation.
10 #ifndef _INDUSTRIAL_IO_H_
11 #define _INDUSTRIAL_IO_H_
13 #include <linux/device.h>
14 #include <linux/cdev.h>
15 #include <linux/iio/types.h>
18 * Provide means of adjusting timer accuracy.
19 * Currently assumes nano seconds.
22 enum iio_chan_info_enum {
23 IIO_CHAN_INFO_RAW = 0,
24 IIO_CHAN_INFO_PROCESSED,
27 IIO_CHAN_INFO_CALIBSCALE,
28 IIO_CHAN_INFO_CALIBBIAS,
30 IIO_CHAN_INFO_PEAK_SCALE,
31 IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW,
32 IIO_CHAN_INFO_AVERAGE_RAW,
33 IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY,
34 IIO_CHAN_INFO_SAMP_FREQ,
35 IIO_CHAN_INFO_FREQUENCY,
37 IIO_CHAN_INFO_HARDWAREGAIN,
38 IIO_CHAN_INFO_HYSTERESIS,
39 IIO_CHAN_INFO_INT_TIME,
57 * struct iio_chan_spec_ext_info - Extended channel info attribute
58 * @name: Info attribute name
59 * @shared: Whether this attribute is shared between all channels.
60 * @read: Read callback for this info attribute, may be NULL.
61 * @write: Write callback for this info attribute, may be NULL.
62 * @private: Data private to the driver.
64 struct iio_chan_spec_ext_info {
66 enum iio_shared_by shared;
67 ssize_t (*read)(struct iio_dev *, uintptr_t private,
68 struct iio_chan_spec const *, char *buf);
69 ssize_t (*write)(struct iio_dev *, uintptr_t private,
70 struct iio_chan_spec const *, const char *buf,
76 * struct iio_enum - Enum channel info attribute
77 * @items: An array of strings.
78 * @num_items: Length of the item array.
79 * @set: Set callback function, may be NULL.
80 * @get: Get callback function, may be NULL.
82 * The iio_enum struct can be used to implement enum style channel attributes.
83 * Enum style attributes are those which have a set of strings which map to
84 * unsigned integer values. The IIO enum helper code takes care of mapping
85 * between value and string as well as generating a "_available" file which
86 * contains a list of all available items. The set callback will be called when
87 * the attribute is updated. The last parameter is the index to the newly
88 * activated item. The get callback will be used to query the currently active
89 * item and is supposed to return the index for it.
92 const char * const *items;
93 unsigned int num_items;
94 int (*set)(struct iio_dev *, const struct iio_chan_spec *, unsigned int);
95 int (*get)(struct iio_dev *, const struct iio_chan_spec *);
98 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
99 uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
100 ssize_t iio_enum_read(struct iio_dev *indio_dev,
101 uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
102 ssize_t iio_enum_write(struct iio_dev *indio_dev,
103 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
107 * IIO_ENUM() - Initialize enum extended channel attribute
108 * @_name: Attribute name
109 * @_shared: Whether the attribute is shared between all channels
110 * @_e: Pointer to an iio_enum struct
112 * This should usually be used together with IIO_ENUM_AVAILABLE()
114 #define IIO_ENUM(_name, _shared, _e) \
117 .shared = (_shared), \
118 .read = iio_enum_read, \
119 .write = iio_enum_write, \
120 .private = (uintptr_t)(_e), \
124 * IIO_ENUM_AVAILABLE() - Initialize enum available extended channel attribute
125 * @_name: Attribute name ("_available" will be appended to the name)
126 * @_e: Pointer to an iio_enum struct
128 * Creates a read only attribute which lists all the available enum items in a
129 * space separated list. This should usually be used together with IIO_ENUM()
131 #define IIO_ENUM_AVAILABLE(_name, _e) \
133 .name = (_name "_available"), \
134 .shared = IIO_SHARED_BY_TYPE, \
135 .read = iio_enum_available_read, \
136 .private = (uintptr_t)(_e), \
140 * struct iio_chan_spec - specification of a single channel
141 * @type: What type of measurement is the channel making.
142 * @channel: What number do we wish to assign the channel.
143 * @channel2: If there is a second number for a differential
144 * channel then this is it. If modified is set then the
145 * value here specifies the modifier.
146 * @address: Driver specific identifier.
147 * @scan_index: Monotonic index to give ordering in scans when read
149 * @scan_type: Sign: 's' or 'u' to specify signed or unsigned
150 * realbits: Number of valid bits of data
151 * storage_bits: Realbits + padding
152 * shift: Shift right by this before masking out
154 * endianness: little or big endian
155 * @info_mask_separate: What information is to be exported that is specific to
157 * @info_mask_shared_by_type: What information is to be exported that is shared
158 * by all channels of the same type.
159 * @event_mask: What events can this channel produce.
160 * @ext_info: Array of extended info attributes for this channel.
161 * The array is NULL terminated, the last element should
162 * have its name field set to NULL.
163 * @extend_name: Allows labeling of channel attributes with an
164 * informative name. Note this has no effect codes etc,
166 * @datasheet_name: A name used in in-kernel mapping of channels. It should
167 * correspond to the first name that the channel is referred
168 * to by in the datasheet (e.g. IND), or the nearest
169 * possible compound name (e.g. IND-INC).
170 * @modified: Does a modifier apply to this channel. What these are
171 * depends on the channel type. Modifier is set in
172 * channel2. Examples are IIO_MOD_X for axial sensors about
174 * @indexed: Specify the channel has a numerical index. If not,
175 * the channel index number will be suppressed for sysfs
176 * attributes but not for event codes.
177 * @output: Channel is output.
178 * @differential: Channel is differential.
180 struct iio_chan_spec {
181 enum iio_chan_type type;
184 unsigned long address;
191 enum iio_endian endianness;
193 long info_mask_separate;
194 long info_mask_shared_by_type;
196 const struct iio_chan_spec_ext_info *ext_info;
197 const char *extend_name;
198 const char *datasheet_name;
202 unsigned differential:1;
207 * iio_channel_has_info() - Checks whether a channel supports a info attribute
208 * @chan: The channel to be queried
209 * @type: Type of the info attribute to be checked
211 * Returns true if the channels supports reporting values for the given info
212 * attribute type, false otherwise.
214 static inline bool iio_channel_has_info(const struct iio_chan_spec *chan,
215 enum iio_chan_info_enum type)
217 return (chan->info_mask_separate & BIT(type)) |
218 (chan->info_mask_shared_by_type & BIT(type));
221 #define IIO_ST(si, rb, sb, sh) \
222 { .sign = si, .realbits = rb, .storagebits = sb, .shift = sh }
224 #define IIO_CHAN_SOFT_TIMESTAMP(_si) \
225 { .type = IIO_TIMESTAMP, .channel = -1, \
226 .scan_index = _si, .scan_type = IIO_ST('s', 64, 64, 0) }
229 * iio_get_time_ns() - utility function to get a time stamp for events etc
231 static inline s64 iio_get_time_ns(void)
235 * calls getnstimeofday.
236 * If hrtimers then up to ns accurate, if not microsecond.
238 ktime_get_real_ts(&ts);
240 return timespec_to_ns(&ts);
243 /* Device operating modes */
244 #define INDIO_DIRECT_MODE 0x01
245 #define INDIO_BUFFER_TRIGGERED 0x02
246 #define INDIO_BUFFER_HARDWARE 0x08
248 #define INDIO_ALL_BUFFER_MODES \
249 (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE)
251 struct iio_trigger; /* forward declaration */
255 * struct iio_info - constant information about device
256 * @driver_module: module structure used to ensure correct
257 * ownership of chrdevs etc
258 * @event_attrs: event control attributes
259 * @attrs: general purpose device attributes
260 * @read_raw: function to request a value from the device.
261 * mask specifies which value. Note 0 means a reading of
262 * the channel in question. Return value will specify the
263 * type of value returned by the device. val and val2 will
264 * contain the elements making up the returned value.
265 * @write_raw: function to write a value to the device.
266 * Parameters are the same as for read_raw.
267 * @write_raw_get_fmt: callback function to query the expected
268 * format/precision. If not set by the driver, write_raw
269 * returns IIO_VAL_INT_PLUS_MICRO.
270 * @read_event_config: find out if the event is enabled.
271 * @write_event_config: set if the event is enabled.
272 * @read_event_value: read a value associated with the event. Meaning
273 * is event dependant. event_code specifies which event.
274 * @write_event_value: write the value associated with the event.
275 * Meaning is event dependent.
276 * @validate_trigger: function to validate the trigger when the
277 * current trigger gets changed.
278 * @update_scan_mode: function to configure device and scan buffer when
279 * channels have changed
280 * @debugfs_reg_access: function to read or write register value of device
283 struct module *driver_module;
284 struct attribute_group *event_attrs;
285 const struct attribute_group *attrs;
287 int (*read_raw)(struct iio_dev *indio_dev,
288 struct iio_chan_spec const *chan,
293 int (*write_raw)(struct iio_dev *indio_dev,
294 struct iio_chan_spec const *chan,
299 int (*write_raw_get_fmt)(struct iio_dev *indio_dev,
300 struct iio_chan_spec const *chan,
303 int (*read_event_config)(struct iio_dev *indio_dev,
306 int (*write_event_config)(struct iio_dev *indio_dev,
310 int (*read_event_value)(struct iio_dev *indio_dev,
313 int (*write_event_value)(struct iio_dev *indio_dev,
316 int (*validate_trigger)(struct iio_dev *indio_dev,
317 struct iio_trigger *trig);
318 int (*update_scan_mode)(struct iio_dev *indio_dev,
319 const unsigned long *scan_mask);
320 int (*debugfs_reg_access)(struct iio_dev *indio_dev,
321 unsigned reg, unsigned writeval,
326 * struct iio_buffer_setup_ops - buffer setup related callbacks
327 * @preenable: [DRIVER] function to run prior to marking buffer enabled
328 * @postenable: [DRIVER] function to run after marking buffer enabled
329 * @predisable: [DRIVER] function to run prior to marking buffer
331 * @postdisable: [DRIVER] function to run after marking buffer disabled
332 * @validate_scan_mask: [DRIVER] function callback to check whether a given
333 * scan mask is valid for the device.
335 struct iio_buffer_setup_ops {
336 int (*preenable)(struct iio_dev *);
337 int (*postenable)(struct iio_dev *);
338 int (*predisable)(struct iio_dev *);
339 int (*postdisable)(struct iio_dev *);
340 bool (*validate_scan_mask)(struct iio_dev *indio_dev,
341 const unsigned long *scan_mask);
345 * struct iio_dev - industrial I/O device
346 * @id: [INTERN] used to identify device internally
347 * @modes: [DRIVER] operating modes supported by device
348 * @currentmode: [DRIVER] current operating mode
349 * @dev: [DRIVER] device structure, should be assigned a parent
351 * @event_interface: [INTERN] event chrdevs associated with interrupt lines
352 * @buffer: [DRIVER] any buffer present
353 * @buffer_list: [INTERN] list of all buffers currently attached
354 * @scan_bytes: [INTERN] num bytes captured to be fed to buffer demux
355 * @mlock: [INTERN] lock used to prevent simultaneous device state
357 * @available_scan_masks: [DRIVER] optional array of allowed bitmasks
358 * @masklength: [INTERN] the length of the mask established from
360 * @active_scan_mask: [INTERN] union of all scan masks requested by buffers
361 * @scan_timestamp: [INTERN] set if any buffers have requested timestamp
362 * @scan_index_timestamp:[INTERN] cache of the index to the timestamp
363 * @trig: [INTERN] current device trigger (buffer modes)
364 * @pollfunc: [DRIVER] function run on trigger being received
365 * @channels: [DRIVER] channel specification structure table
366 * @num_channels: [DRIVER] number of channels specified in @channels.
367 * @channel_attr_list: [INTERN] keep track of automatically created channel
369 * @chan_attr_group: [INTERN] group for all attrs in base directory
370 * @name: [DRIVER] name of the device.
371 * @info: [DRIVER] callbacks and constant info from driver
372 * @info_exist_lock: [INTERN] lock to prevent use during removal
373 * @setup_ops: [DRIVER] callbacks to call before and after buffer
375 * @chrdev: [INTERN] associated character device
376 * @groups: [INTERN] attribute groups
377 * @groupcounter: [INTERN] index of next attribute group
378 * @flags: [INTERN] file ops related flags including busy flag.
379 * @debugfs_dentry: [INTERN] device specific debugfs dentry.
380 * @cached_reg_addr: [INTERN] cached register address for debugfs reads.
389 struct iio_event_interface *event_interface;
391 struct iio_buffer *buffer;
392 struct list_head buffer_list;
396 const unsigned long *available_scan_masks;
398 const unsigned long *active_scan_mask;
400 unsigned scan_index_timestamp;
401 struct iio_trigger *trig;
402 struct iio_poll_func *pollfunc;
404 struct iio_chan_spec const *channels;
407 struct list_head channel_attr_list;
408 struct attribute_group chan_attr_group;
410 const struct iio_info *info;
411 struct mutex info_exist_lock;
412 const struct iio_buffer_setup_ops *setup_ops;
414 #define IIO_MAX_GROUPS 6
415 const struct attribute_group *groups[IIO_MAX_GROUPS + 1];
419 #if defined(CONFIG_DEBUG_FS)
420 struct dentry *debugfs_dentry;
421 unsigned cached_reg_addr;
426 * iio_find_channel_from_si() - get channel from its scan index
428 * @si: scan index to match
430 const struct iio_chan_spec
431 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si);
434 * iio_device_register() - register a device with the IIO subsystem
435 * @indio_dev: Device structure filled by the device driver
437 int iio_device_register(struct iio_dev *indio_dev);
440 * iio_device_unregister() - unregister a device from the IIO subsystem
441 * @indio_dev: Device structure representing the device.
443 void iio_device_unregister(struct iio_dev *indio_dev);
446 * iio_push_event() - try to add event to the list for userspace reading
447 * @indio_dev: IIO device structure
448 * @ev_code: What event
449 * @timestamp: When the event occurred
451 int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp);
453 extern struct bus_type iio_bus_type;
456 * iio_device_put() - reference counted deallocation of struct device
457 * @indio_dev: IIO device structure containing the device
459 static inline void iio_device_put(struct iio_dev *indio_dev)
462 put_device(&indio_dev->dev);
466 * dev_to_iio_dev() - Get IIO device struct from a device struct
467 * @dev: The device embedded in the IIO device
469 * Note: The device must be a IIO device, otherwise the result is undefined.
471 static inline struct iio_dev *dev_to_iio_dev(struct device *dev)
473 return container_of(dev, struct iio_dev, dev);
477 * iio_device_get() - increment reference count for the device
478 * @indio_dev: IIO device structure
480 * Returns: The passed IIO device
482 static inline struct iio_dev *iio_device_get(struct iio_dev *indio_dev)
484 return indio_dev ? dev_to_iio_dev(get_device(&indio_dev->dev)) : NULL;
489 * iio_device_set_drvdata() - Set device driver data
490 * @indio_dev: IIO device structure
491 * @data: Driver specific data
493 * Allows to attach an arbitrary pointer to an IIO device, which can later be
494 * retrieved by iio_device_get_drvdata().
496 static inline void iio_device_set_drvdata(struct iio_dev *indio_dev, void *data)
498 dev_set_drvdata(&indio_dev->dev, data);
502 * iio_device_get_drvdata() - Get device driver data
503 * @indio_dev: IIO device structure
505 * Returns the data previously set with iio_device_set_drvdata()
507 static inline void *iio_device_get_drvdata(struct iio_dev *indio_dev)
509 return dev_get_drvdata(&indio_dev->dev);
512 /* Can we make this smaller? */
513 #define IIO_ALIGN L1_CACHE_BYTES
515 * iio_device_alloc() - allocate an iio_dev from a driver
516 * @sizeof_priv: Space to allocate for private structure.
518 struct iio_dev *iio_device_alloc(int sizeof_priv);
520 static inline void *iio_priv(const struct iio_dev *indio_dev)
522 return (char *)indio_dev + ALIGN(sizeof(struct iio_dev), IIO_ALIGN);
525 static inline struct iio_dev *iio_priv_to_dev(void *priv)
527 return (struct iio_dev *)((char *)priv -
528 ALIGN(sizeof(struct iio_dev), IIO_ALIGN));
532 * iio_device_free() - free an iio_dev from a driver
533 * @indio_dev: the iio_dev associated with the device
535 void iio_device_free(struct iio_dev *indio_dev);
538 * devm_iio_device_alloc - Resource-managed iio_device_alloc()
539 * @dev: Device to allocate iio_dev for
540 * @sizeof_priv: Space to allocate for private structure.
542 * Managed iio_device_alloc. iio_dev allocated with this function is
543 * automatically freed on driver detach.
545 * If an iio_dev allocated with this function needs to be freed separately,
546 * devm_iio_device_free() must be used.
549 * Pointer to allocated iio_dev on success, NULL on failure.
551 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv);
554 * devm_iio_device_free - Resource-managed iio_device_free()
555 * @dev: Device this iio_dev belongs to
556 * @indio_dev: the iio_dev associated with the device
558 * Free iio_dev allocated with devm_iio_device_alloc().
560 void devm_iio_device_free(struct device *dev, struct iio_dev *indio_dev);
563 * devm_iio_trigger_alloc - Resource-managed iio_trigger_alloc()
564 * @dev: Device to allocate iio_trigger for
565 * @fmt: trigger name format. If it includes format
566 * specifiers, the additional arguments following
567 * format are formatted and inserted in the resulting
568 * string replacing their respective specifiers.
570 * Managed iio_trigger_alloc. iio_trigger allocated with this function is
571 * automatically freed on driver detach.
573 * If an iio_trigger allocated with this function needs to be freed separately,
574 * devm_iio_trigger_free() must be used.
577 * Pointer to allocated iio_trigger on success, NULL on failure.
579 struct iio_trigger *devm_iio_trigger_alloc(struct device *dev,
580 const char *fmt, ...);
583 * devm_iio_trigger_free - Resource-managed iio_trigger_free()
584 * @dev: Device this iio_dev belongs to
585 * @iio_trig: the iio_trigger associated with the device
587 * Free iio_trigger allocated with devm_iio_trigger_alloc().
589 void devm_iio_trigger_free(struct device *dev, struct iio_trigger *iio_trig);
592 * iio_buffer_enabled() - helper function to test if the buffer is enabled
593 * @indio_dev: IIO device structure for device
595 static inline bool iio_buffer_enabled(struct iio_dev *indio_dev)
597 return indio_dev->currentmode
598 & (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE);
602 * iio_get_debugfs_dentry() - helper function to get the debugfs_dentry
603 * @indio_dev: IIO device structure for device
605 #if defined(CONFIG_DEBUG_FS)
606 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
608 return indio_dev->debugfs_dentry;
611 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
617 int iio_str_to_fixpoint(const char *str, int fract_mult, int *integer,
621 * IIO_DEGREE_TO_RAD() - Convert degree to rad
622 * @deg: A value in degree
624 * Returns the given value converted from degree to rad
626 #define IIO_DEGREE_TO_RAD(deg) (((deg) * 314159ULL + 9000000ULL) / 18000000ULL)
629 * IIO_G_TO_M_S_2() - Convert g to meter / second**2
632 * Returns the given value converted from g to meter / second**2
634 #define IIO_G_TO_M_S_2(g) ((g) * 980665ULL / 100000ULL)
636 #endif /* _INDUSTRIAL_IO_H_ */